I think revit is a great program. Even though I just started 4 to 5 months ago learning revit, I was able to make design changes in front of the client utilizing the 3d modelling aspect. One suggestion that would be a great benefit would be the ability to easily change eaves and rafter tails on a roof. I think roof detailing should be important and the ability to have customizable roofs that have preattached custom eaves and rafter tails would be a great benefit to the program. The ability to create a residential roof and quickly click between say tuscany rafter tails or mediterranean cornice or even traditional fascia would be very helpful. Basically allow you to create a roof the way a roof is built. With all the detail, but quickly without having to make a custom roof profile or a void.